I've just done my annual (or bi-annual) descaling of my Andreja Premium using the advice from this forum on detatching the water level probe during refill.

After finishing up everything, the boiler gauge now reads off the scale - i.e. above 3 bar - when heated up fully. It appears to showing the pressure much higher than it actually is. I've tried adjusting the steam pressure down to just below what reads as just below 2.5 bar but the machine looses steam very quickly with this setting.

Could the descaling process have broken or somehow offset the boiler pressure sensor?

Thanks,
C

The good thing is that it sounds like your pressure-stat is working, and you seem to be able to judge the pressure based on steaming performance. Is it possible that the gauge saw an overpressure during the (manual) boiler-fill operation? That could deflect it permanently upscale, making replacement necessary.

Thanks David,

So that would mean replacing this one: http://www.chriscoffee.com/Boiler_Press ... bpgqml.htm

There is no way of resetting the existing gauge?

C

There probably is a way of resetting the existing gage BUT that is far from the problem.

From what you have written, it seems as though "something" found its way into the 6 mm line connecting the pstat to the boiler. This "something" blocked or partially blocked the line such that your pstat did not know whether it was coming or going - hence the 3.0 bar pressure which should have easily caused your boiler's safety valve to open (1.8 bar IIRC).

My "top of the head" recommendation - take the line leading to the pstat off and soak it in a descaling solution. Put a few drops of white vinegar into the pstat itself using a syringe or equivalent. Rinse all components and restart, paying close attention to the on/off switch and the boiler pressure gage.

Thanks Eric.

I take it I should take the pstat out of the machine before attempting any vinegar insertion?

Cheers,
C

Yes.

The tubing gets the inspection/descaling and the pstat gets the vinegar.

Sorry - forgot to post my other question: I assume that you are referring to the thicker tube leading from the bottom of the pstat to the probe on top of the boiler - not the thin long tube leading from the probe to the gauge?

C

From reading the original post, it appears as though the safety release never activated, and at 2.5 bar on the scale, there is little steam.

Either the gauge is working correctly and the pressure is really getting that high and the safety isn't opening, which is a dangerous situation, or the gauge is way off, pressure is correct, only a cosmetic/operational problem.

Given the low steam pressure with a reading of 2.5 bar, I'd lean towards a defective gauge, however the ultimate approach depends upon the comfort level of the machine owner with dealing with a potentially explosive situation.

If it were me, I'd get a gauge I could put on the steam wand and turn on the machine with the wand open (connected to the independent gauge). Then I could watch both gauges as pressure builds and see if anything is inconsistent with the reading.

If not, then fix the pressurestat.
If so, and pressure gets to the expected level on the steamingwand gauge then fix/replace the machine gauge.

I'm pretty certain the gauge is not working correctly. The steam pressure at what is read as almost 3 bar is on the low side and the steam gauge still reads about 1.8 bar when the machine is off and I've let all the water I can out of via the hot water wand.

So it appears the calibration is off and that ~1.8 bar is actually zero.

In any case, I'll check the tubes leading from the pstat to the sensor as per Eric's suggestion as well as the one leading from the sensor to the gauge.

If that fails, I guess a new gauge is next.

Good catch. Now that you reminded me, yes, I would soak that capillary tubing to the gage also.

I agree with what Allon says and just checked the Andreja parts list which shows the safety valve opening pressure as 3.0 bar - /downloads/ ... _Parts.pdf

Certainly, the boiler pressure gage should return to zero when all connections are loose. By itself, that is not 100% assurance that the gage is correct but is a reasonable indicator.